The invention relates to a box-like container for flat mailings in an upright position, having a stack support that can be removed from the container open at the top, and having a base, two narrow end walls and two lateral longitudinal walls. The mailings are aligned in the container with their large sides toward the end walls.
Modern letter sorting systems reach peak throughputs of up to approx. 45,000 mailings per hour. Emptying is generally carried out manually, that is to say the sorted stacks of mailings are transferred from the sorter into mail containers by hand. The mail containers themselves are then either stacked manually on trolleys or transferred to modern tray management systems. This manual process is associated with a high error rate of the operator, a high monotonous loading on the operator and very low throughputs.
When the mailings are fed into the sorter, there is generally likewise a manual transfer from containers to the separating apparatus of the sorter.
A further increase in output would therefore require additional operating personnel and therefore reduce the profitability of the sorting system.
In EP 0 109 325, FR 2 621 297, mail containers needed for this purpose are described. These consist of plastic (PP) and have various reinforcements in order to achieve the necessary dimensional stability. These containers are shaped in such a way that, given mutual alignment with one another and with an alignment rotated through 180° about the vertical axis in relation to one another, they can be stacked in one another.
In this connection, a container that is suitable for flat mailings in an upright position has been disclosed (DE 89 13 760 U1), whose inner sides of the lateral longitudinal walls have elongated recesses open at the top and running in straight lines at regular intervals at right angles to the base for a removable stack support which, in the longitudinal direction of the lateral longitudinal walls, are wider than their slot-like openings toward the interior of the container. At its two lateral ends, the stack support has shaped elements which can be pushed into the elongated recesses through the slot-like openings with a form-fitting connection only at right angles to the base. These recesses are wider in the longitudinal direction of the lateral longitudinal walls than their slot-like openings. In U.S. Pat. No. 3,200,983, the recesses are formed as dovetail guides.
For further increases in throughput, the development of automatic filling and emptying machines and the mail transport containers suitable for this purpose are required.
For this purpose, what is known as the mail cartridge system (MCS) is known (U.S. Pat. No. 6,026,967, WO 97/36523), in which use is made of a specific container which, itself formed as a stacking compartment, is suspended directly on the sorter in front of the stacking mechanism. The sorting is carried out directly in the cartridge-like container without a transfer process. After the sorting process has been completed, the cartridge is removed by a robot on the sorter, replaced by an empty cartridge and transferred to a buffer or transport system. The disadvantages inherent to the MCS system are, firstly, the complex and heavy cartridge, on account of the high functional integration, the considerably increased transport costs, the lack of any ability to be stacked and nested, restricted suitability for air freight and, secondly, the low filling rates of the containers. These cannot subsequently be filled with mailed goods.
The invention is based on the object of providing a box-like container having a removal stack support in order to hold and to transport flat mailings, in which, in spite of side walls with a low rigidity, secure retention of the stack support absorbing the stacking pressure is ensured in various positions corresponding to the stack size, and which prevents uncontrolled slippage of the mailings at right angles to the stacking direction.